STUDY ON PRESTABILIZATION OF PUMPKIN (CUCURBITA MOSCHATA) BY OSMOTIC DEHYDRATION IN QUATERNARY COMPLEX SOLUTION

Pumpkin is a very appreciated vegetable for both unique sensory characteristics and significant content of substances with healthy effects. Very few “pumpkin-processed foods” with adequate shelf life are available on the market because of poor knowledge relative to its behavior during industrial processes. The possibility to reduce water activity (Aw) and pH of pumpkin samples by osmotic treatment in complex (quaternary) solution was studied by response-surface methodology (RSM). The reduction of pH and Aw until values recognized as safe for spore germination of Clostridium botulinum and Clostridium perfringens was respectively obtained without significant color degradation. Moreover, the modulation of the independent variables, carried out by using the best-fit equation, was aimed at prestabilizing pumpkin creams. PRACTICAL APPLICATIONS The poor knowledge concerning the behavior of pumpkins during industrial processing reduces their uses to produce a variety of “pumpkin food” with adequate shelf life. In this article, the possibility of applying an osmotic treatment in a complex (quaternary) solution in order to simultaneously obtain a reduction in water activity (Aw) and pH was presented. In addition, the utilization of model equation allows the simulation of osmotic dehydration, giving information on the process conditions usable to reach Aw and pH values recognized as risk threshold for spore germination of Clostridium botulinum and Clostridium perfringens.